Tuyere structure for underfeed stokers



a- ,1 magma $2. L. @EERS V TUYERE swucwan FOR UNDERFEED s'roxmns Original Filed Juns 16, 1922 2 Shasta-sham i l/a w Aug. 17 1926. 1,595,986

R. L,. BEERS TUYERE STRUCTURE FOR UNDERF'EED STOKERS Origi al Filed June 16, 1922 2 Sheets-Shoot 2 ,1727/572 zar." $ayce ,ZLIE Z Patented Aug. 17, 1926.

UNITED STATES aren't orricE.

ROYCE L. BEERS, OF DETROIT, MICHIGAN, ASSIG NOR, BY MESNE ASSIGNMENTS, TO

RILEY STOKER CORPORATION, OF WORCESTER, MASSACHUSETTS, .A- CORPORA- TION OF MASSACHUSETTS.

TUYERE STRUCTURE FOR UNDERFEED STOKERS.

Original application filed .Tune 16, 1922, Serial No. 568,797. Divided and this application filed August My present inventionin tuyere structures has particularly to do, in some of its aspects, with stokers wherein a plurality of laterally extending retorts open into a longitudinal main retort at and below the top-margins of the retort castings, one form of such stoker being shown in my co-pending application Serial No. 568,797, filed June 16, 1922, of which this case is a division.

Among the objects of my invention are to provide a corner-tuyere structure for use as described, which has great strength, heatresistivity, adequacy of air-distribution, simplicity and economy in initial construction, facility for renewal or replacement of damaged parts, and ability to function with out substantial detriment to the operation of the stoker even when the tuyere structure is partially destroyed. Other and further objects will become apparent to those skilled in the art from the following disclosure.

To these ends my invention consists in the features of construction and combinations and arrangements of parts hereinafter more particularly described and claimed.

In the drawing Fig. 1 is a horizontal section through a stoker-equipped furnace, with parts broken away; Fig. 1 is a fragmentary sectional View on the line aa of Fig. 1. Fig. 2 is a vertical section through a corner postand tuyere structure, taken on line 22 of Figs. 1 and 3; Fig. 3 is a section on line 83 of Fig. 2; and Fig. 4 is a perspective view of the corner-tuyere structure.

As to the general construction of the stoker illustrated, it will be understood that green fuel from a supply hopper 10 is fed through a front-wall throat 11 into a main longiti'idinal retort 12 by the reciprocation of a' suitable ram appropriately driven as by ramengine 1 1, in known fashion. The green fuel thus fed into the main retort 12 is, in part, ultimately consumed in the combustion area directly abqve the main retort, but other portions of the fuel, (more or less affected by the passage through the main retort) will be distributed to lateral retorts 15 for consumption in the further area served by these retorts. Of these lateral retorts a suitable plurality may be provided, dependent on the length of the main retort and the de- Serial No. 657,684.

sired width of each lateral retort. The particular installation shown provides lateral retorts at one side only of the main retort, but of course my present invention is not restricted in this regard.

These several retort structures of course form part of a fire-box floor which as a whole extends from the front wall 17 to the bridge wall 18, and from one side wall 19 to the other side wall 20 of the boilersetting, and it will of course be understood that, consistently with usual practice, air under pressure is admitted beneath the retorts for distribution through the tuyereopenings, generically indicated at 26, around the margins of the retort structure, to supportcombustioii within the fire-box.

Since the lateral retorts open to the main retort at and below the upper margins of the retort-casting, a sidewall of the main retort 12 takes form as a series of posts '1' 8, each such post comprising as its end surface a portion of the side wall of the main retort. and as its two side surfaces respective portions of the side walls of two adjoining lateral retorts, the laterally-extending retorts being spaced apart somewhat to leave therebetween air-trunks 83, each such air trunk being spanned by suitable tuyere blocks 82, which preferably are of plate form, disposed in generally upright arrangement side by side, to rest on the flanged side-margins of the retort-casting, and supplemented by corner-tuyere structures 84c forming the tops of the side wall posts. Such corner-tuyeres especially form the subject of the present case.

Any corner tuyere employed at such a place in a stoker as described is especially subject to hard usage and to extreme conditions tending to its destruction. Constantly subjected to high temperatures, called upon to supply air adequately toward both branch retorts and toward the main retort, and in position subjecting them to coal-pressure due to the cross-currents of fuel flow in the longitudinal feeding of the fuel to the main retort and its diversion into the lateral retorts, these corner tuyeres are called upon to act under very severe conditions, and their failure of operation is of especially serious detriment to the operation of the stoker.

In the corner tuyere structure shown I provide a plurality of complemental thin sections, interlocking to give firm assembly and shaped in the aggregate to present in their upper portion rounded contour, near ly quarter-sphericalin extent, for exposure to the fire, with tuyere openings in all directions of such quarter spherical surface, these sections being sh-ueo at their lower portions to make up a stem for insertion into the a u k ims be een two lateral re rts- In detail, five sections or layers are. shown, although more or less may be used, these sections 84: 84:, 84-, 8a and 8 9, having each a head portion (85 to 85) and a stem portion (86 to 86 Each section has a plate-web (87 to 87) marginally bordered throughout the exposed head part by a flange-rim (88 to 88 through which flanges the tuye're-openings 26 are made, each leading to an interspace between adjacent body webs, so that in the assembly the associated sections present a smooth exterior contour interrupted only by the said tuyere openings 26. The stem portions have interlocking and spacing lugs (8.9 to 89 formed as short edge-flanges thereon, to contact one with another for p0- sitioning the layers in assembled relation with the lower portions of the body webs substantially parallel, the positions of such lugs being preferably such that not only is a bottom opening left free for ingress of air to the interspaces between the head-portions, but side openings may also be left between the webs of the longer sections. Preferably all of the stems will be notched, as at 90, immediately below the heads of the respective sections, for engagement with the flanges 78 marginally bordering the adjacent lateral retorts, such flanges preferably having therein notches 90 to facilitate insertion of the tuyere-sections in erection or replacement of the parts.

The surfaces of severance or cleavage between the layers or sections of the corner tuyere are preferably nearly parallel between the stem portions, but through the heads preferably sweep on curves of progressively shorter radius for uniform distribution of the tuyere openings and stronger interlock of the parts. Also it is preferred that the stem portions of the sections nearest the end or front of the posts may be short, and the stems of the sections more remote from that end shall be longer, for economy in construction, mechanical adequacy of anchorage and interlocking effect to resist the strain imposed on the heads of varying heights, and beneficial tendency toward apportionment of air distribution.

It will. be observed that each tuyere section or layer provides a head portion or" great ruggedness, integrally connected with its heat-conductive stem which will be constantly subjectedto the cooling influence of the air flowing through the relatively narrow or flat interspaces or channels, so that the heat-resistivity of the construction is great, and further that even should a portion of the corner tuyere be burned away, notwithstanding its heatenduring construction, the stem-portions will themselves afford a grid which will uphold the fuel and afford a measurable directional distribution of the air, enabling the stoker to be con tinued in operation if necessary without eX- cessive detriment to the stoker or creation of a hole in the fire.

While I have herein described in some deail a particular construction of particular advantage, for purposes of full disclosure, it will be understood by those skilled in the art that in its broader aspects my invention is not limited to the precise details shown and described, and that many changes in particular construction and arrangement of parts may be made without departure from the spirit of my invention within the scope of the appended claims.

I claim:

1. In an under-feed stoker, having a main retort with side openings separated by posts, and having lateral retorts communicating with said openings, and having between adjoining lateral retorts spaces constituting air trunks, a corner-tuyere structure for such a post comprising a plurality of sections jointly presenting a working surface of approximately quarter-spherical form, each of said sections comprising a head portion and a stem portion, and said sections providing air spaces between their stems and opening through said surface of the heads.

2. A multi-sectioned corner-tuyere structure for an underfeed stoker, comprising a plurality of sections each having a head portion to present a part of the working surface and a stem portion to extend into an air trunk, aid head portions jointly presenting a working surface of approximately quarter-spherical form and having tuyere-openings between said sections.

3. A multi-sectioned corner-tuyere structure for an underfeed stoker, comprising a plurality of section each having a head portion to present a part of the working surface and a stem portion to extend into an air trunk, said head portions jointly presenting a curved working surface of approximately quarter-spherical form and having tuyere-openings between the sections, and said stein portions having open spaces between the sections to supply air to the tuyere-openings.

i. A multisection corner-tuyere structure having a working surface of generally partispherical'curvature, and divided into sections on curved surfaces of cleavage which are respectively of different radii.

5. A multisection corner-tuyere structure 6. Structure as set forth in claim 8, Wherei in the stems are of different lengths, increasing in length toward the discharge sideof the stoker.

7. A Inulti-sectioned corner-tuyre structure having a working surface of approximately quarter-spherical form comprising a plurality of sections each having a stem portion and a head portion, the surface of cleavage of the head portions non-aligning with the surfaces of cleavage of the stem portions.

8. Structure as set forth in claim 7 Where-' in each two adjacent sections form an air passage therebetween, and adjacent heads are formed with 'complementa-l notches to afford tuyre-openings communicating With 20 said air passages.

ROYCE L. BEERS. 

